The installation and removal of workpieces, including springs, frequently requires expansion and/or manipulation of the workpiece. Workpieces of particular pertinence to the present invention are coil springs.
The installation and removal of springs frequently requires expansion and/or manipulation of the spring to attach or remove spring hooks to or from pins or to insert or remove spring hooks into or from apertures. Such pins or apertures are often inaccessible and additionally require the spring to be expanded as it is manipulated. The location of such pins or apertures may require the spring hook to be unobstructed by a tool-head or arm thus limiting the tool-head or arm contact with the spring to the spring shank in order to facilitate hooking, insertion or removal or even to permit hooking, insertion or removal of the spring hook.
A spring shank may have an inclined or angular offset or an inline shoulder between the spring hook and spring coil. The shank configuration often interferes with the ability of an expansion tool to grasp the spring in attempting to expand or manipulate the spring.
The stiffness and strength of a spring may determine the potential for both the difficulty in expansion and manipulation for installation and/or removal and for injury should the spring, the tool or the operator slip during installation and/or removal. Heavy duty springs often require exertion of substantial mechanical leverage resulting in considerable stored energy which, if inadvertently released by the lever or tool slipping, may cause difficulty in spring installation or removal and additionally may cause the lever or tool operator to be injured or allow the spring to strike the operator causing injury. Thus it is desirable to have the spring, in its expanded stored energy position, to be secured or grasped at both spring shanks or hooks in order to control and reduce the potential for slipping, thereby facilitating installation, removal or manipulation and reducing the opportunities for injury.
However, the strength of the spring may be of secondary or even of no consequence when the anchoring structure is inaccessible or the spring is light duty in nature. In such event the ability to secure or grasp both spring shanks can give the greatest control for ease of manipulation as required for spring installation or removal. Thus, securing or grasping both spring shanks insures safer spring manipulation while simultaneously increasing control for spring installation and removal. The present invention secures or grasps both spring shanks by wedging the spring shank between the tines of a furcated jaw and the bearing surface of an upstanding arm which is affixed to one of the tines.
Other expansion tools used to expand and manipulate brake springs are now identified as related art and are disclosed in accordance with 37 CFR 1.97 as follows: The Spring Engaging Hook Assembly for Brake Spring Tools shown in U.S. Pat. No. 2,507,622 to Frank J. Brugmann; the Brake Spring Tool shown in U.S. Pat. No. 2,522,611 to R. N. Guth; the Spring Manipulating Tool shown in U.S. Pat. No. 1,953,930 to B. E. Dyal; the Brake Cable Release Tool shown in U.S. Pat. No. 3,540,106 to M. J. Goldman; the Spring Expander shown in U.S. Pat. No. 2,329,591 to H. C. Christian, and the Spring Expanding Device shown in U.S. Pat. No. 1,951,953 to J. Tollonitsch. Each known patent is noted to have partially addressed these long recognized problems of safety and control but has failed to provide the solution or meet the improvement found in the present invention.
The Rockwell Q-Series Brake or Q-Series Brake, manufactured by Rockwell International Automotive, Troy, Michigan, 48084 and other manufacturers, U.S. Pat. No. Re. 31,531, Mar. 6, 1984, is used in many heavy truck and bus brake assemblies and employs two heavy duty retaining springs to retain the assembly brake shoes in their proper position. The retaining springs have spring shanks with an inline shoulder between the spring hook and spring coil. The principal present method of retaining spring installation for the Rockwell Q-Series Brake assembly is accomplished by the operator attaching a pair of locking pliers to one of the spring shanks. The opposing spring hook is inserted in an aperture in one brake shoe. A screwdriver or a bar is then employed as a lever, utilizing the axle spindle or axle housing as the fulcrum, to move the pliers and hence expand the retaining spring to permit insertion of the spring hook in an aperture of a second brake shoe. The instability inherent in the use of such a lever renders installation difficult and frequently results in injury to the operator's hands and fingers. Operators presently have no tool which controls the retaining spring in its expanded state. An expansion tool permitting such control is needed within the industry to both facilitate the installation and removal of the retaining springs and to reduce the potential for injury during the process of spring manipulation and installation. The present invention is particularly adapted to accommodate the retaining springs utilized by the Rockwell Q-Series Brake.